Prevents galvanic corrosion caused by galvanic current flow when plugged into shore power.
The Index Marine Galvanic Isolator is a device used on boats to mitigate galvanic corrosion, a type of electrochemical corrosion that can occur when dissimilar metals are immersed in water (especially saltwater).
Galvanic isolators play a key role in the prevention of expensive and potentially dangerous corrosive damage to metalwork on boats in contact with water such as hulls, rudders, propellors, shafts and tubes.
When a boat is connected to shore power, the ground wire provides safety in case of electrical faults. However, this wire can also create a conductive path for low-voltage DC currents caused by galvanic action between different boats or the marina's infrastructure.
The isolator is installed in the shore power earth wire (ground wire) circuit. It uses diodes to block low-voltage galvanic currents (usually less than 1.4 volts) while allowing higher voltage currents to pass through for safety.
By preventing galvanic currents, it stops the accelerated corrosion of metal components without compromising the electrical safety of the system
Galvanic Isolators are also known as zinc savers.
Variants are available to cater for 16Amp, 32 Amp shore and vessel electrical systems. The appropriate variant should be installed in-line in the earth cable between where shore power enters the boat and the vessels electrical distribution panel. All vessels will benefit from the installation of a correctly installed galvanic isolator, and many marinas including all in the US make their use mandatory.